diff options
Diffstat (limited to 'sys/dev/random')
| -rw-r--r-- | sys/dev/random/harvest.c | 77 | ||||
| -rw-r--r-- | sys/dev/random/hash.c | 2 | ||||
| -rw-r--r-- | sys/dev/random/randomdev.c | 46 | ||||
| -rw-r--r-- | sys/dev/random/yarrow.c | 65 | ||||
| -rw-r--r-- | sys/dev/random/yarrow.h | 10 |
5 files changed, 139 insertions, 61 deletions
diff --git a/sys/dev/random/harvest.c b/sys/dev/random/harvest.c index 4bfac55..2f9ac2b 100644 --- a/sys/dev/random/harvest.c +++ b/sys/dev/random/harvest.c @@ -31,30 +31,38 @@ #include <sys/types.h> #include <sys/queue.h> #include <sys/kthread.h> +#include <sys/poll.h> +#include <sys/select.h> #include <sys/random.h> #include <sys/time.h> +#include <machine/mutex.h> #include <crypto/blowfish/blowfish.h> -#include <dev/randomdev/hash.h> -#include <dev/randomdev/yarrow.h> +#include <dev/random/hash.h> +#include <dev/random/yarrow.h> + +static u_int read_random_phony(void *, u_int); /* hold the address of the routine which is actually called if * the ramdomdev is loaded */ -static void (*reap)(struct timespec *, void *, u_int, u_int, u_int, u_int) = NULL; +static void (*reap_func)(struct timespec *, void *, u_int, u_int, u_int, u_int) = NULL; +static u_int (*read_func)(void *, u_int) = read_random_phony; /* Initialise the harvester at load time */ void -random_init_harvester(void (*reaper)(struct timespec *, void *, u_int, u_int, u_int, u_int)) +random_init_harvester(void (*reaper)(struct timespec *, void *, u_int, u_int, u_int, u_int), u_int (*reader)(void *, u_int)) { - reap = reaper; + reap_func = reaper; + read_func = reader; } /* Deinitialise the harvester at unload time */ void random_deinit_harvester(void) { - reap = NULL; + reap_func = NULL; + read_func = read_random_phony; } /* Entropy harvesting routine. This is supposed to be fast; do @@ -67,25 +75,60 @@ random_harvest(void *entropy, u_int count, u_int bits, u_int frac, u_int origin) { struct timespec timebuf; - if (reap) { + if (reap_func) { nanotime(&timebuf); - (*reap)(&timebuf, entropy, count, bits, frac, origin); + (*reap_func)(&timebuf, entropy, count, bits, frac, origin); } } -/* Helper routines to enable kthread_exit() to work while the module is - * being (or has been) unloaded. +/* Userland-visible version of read_random */ +u_int +read_random(void *buf, u_int count) +{ + return (*read_func)(buf, count); +} + +/* If the entropy device is not loaded, make a token effort to + * provide _some_ kind of randomness. This should only be used + * inside other RNG's, like arc4random(9). */ -void -random_set_wakeup(int *var, int value) +static u_int +read_random_phony(void *buf, u_int count) { - *var = value; - wakeup(var); + struct timespec timebuf; + u_long randval; + int size, i; + static int initialised = 0; + + /* Try to give random(9) a half decent initialisation + * DO not make the mistake of thinking this is secure!! + */ + if (!initialised) { + nanotime(&timebuf); + srandom((u_long)(timebuf.tv_sec ^ timebuf.tv_nsec)); + } + + /* Fill buf[] with random(9) output */ + for (i = 0; i < count; i+= sizeof(u_long)) { + randval = random(); + size = (count - i) < sizeof(u_long) ? (count - i) : sizeof(u_long); + memcpy(&((char *)buf)[i], &randval, size); + } + + return count; } +/* Helper routine to enable kthread_exit() to work while the module is + * being (or has been) unloaded. + * This routine is in this file because it is always linked into the kernel, + * and will thus never be unloaded. This is critical for unloadable modules + * that have threads. + */ void -random_set_wakeup_exit(int *var, int value, int exitval) +random_set_wakeup_exit(void *control) { - random_set_wakeup(var, value); - kthread_exit(exitval); + wakeup(control); + mtx_enter(&Giant, MTX_DEF); + kthread_exit(0); + /* NOTREACHED */ } diff --git a/sys/dev/random/hash.c b/sys/dev/random/hash.c index 432a54b..47bf7c2 100644 --- a/sys/dev/random/hash.c +++ b/sys/dev/random/hash.c @@ -35,7 +35,7 @@ #include <sys/types.h> #include <crypto/blowfish/blowfish.h> -#include <dev/randomdev/hash.h> +#include <dev/random/hash.h> /* initialise the hash by copying in some supplied data */ void diff --git a/sys/dev/random/randomdev.c b/sys/dev/random/randomdev.c index d6796ef..eaa47b9 100644 --- a/sys/dev/random/randomdev.c +++ b/sys/dev/random/randomdev.c @@ -36,20 +36,24 @@ #include <sys/malloc.h> #include <sys/module.h> #include <sys/bus.h> +#include <sys/poll.h> #include <sys/proc.h> +#include <sys/select.h> #include <sys/random.h> +#include <sys/vnode.h> #include <machine/bus.h> #include <machine/resource.h> #include <sys/sysctl.h> #include <crypto/blowfish/blowfish.h> -#include <dev/randomdev/hash.h> -#include <dev/randomdev/yarrow.h> +#include <dev/random/hash.h> +#include <dev/random/yarrow.h> static d_open_t random_open; static d_read_t random_read; static d_write_t random_write; static d_ioctl_t random_ioctl; +static d_poll_t random_poll; #define CDEV_MAJOR 2 #define RANDOM_MINOR 3 @@ -61,7 +65,7 @@ static struct cdevsw random_cdevsw = { /* read */ random_read, /* write */ random_write, /* ioctl */ random_ioctl, - /* poll */ nopoll, + /* poll */ random_poll, /* mmap */ nommap, /* strategy */ nostrategy, /* name */ "random", @@ -105,13 +109,22 @@ random_read(dev_t dev, struct uio *uio, int flag) int error = 0; void *random_buf; - c = min(uio->uio_resid, PAGE_SIZE); - random_buf = (void *)malloc(c, M_TEMP, M_WAITOK); - while (uio->uio_resid > 0 && error == 0) { - ret = read_random(random_buf, c); - error = uiomove(random_buf, ret, uio); + if (flag & IO_NDELAY && !random_state.seeded) { + error = EWOULDBLOCK; + } + else { + if (random_state.seeded) { + c = min(uio->uio_resid, PAGE_SIZE); + random_buf = (void *)malloc(c, M_TEMP, M_WAITOK); + while (uio->uio_resid > 0 && error == 0) { + ret = read_random_real(random_buf, c); + error = uiomove(random_buf, ret, uio); + } + free(random_buf, M_TEMP); + } + else + error = tsleep(&random_state, 0, "rndblk", 0); } - free(random_buf, M_TEMP); return error; } @@ -141,6 +154,21 @@ random_ioctl(dev_t dev, u_long cmd, caddr_t addr, int flags, struct proc *p) } static int +random_poll(dev_t dev, int events, struct proc *p) +{ + int revents; + + revents = 0; + if (events & (POLLIN | POLLRDNORM)) { + if (random_state.seeded) + revents = events & (POLLIN | POLLRDNORM); + else + selrecord(p, &random_state.rsel); + } + return revents; +} + +static int random_modevent(module_t mod, int type, void *data) { int error; diff --git a/sys/dev/random/yarrow.c b/sys/dev/random/yarrow.c index 1360d8e..fe4d160 100644 --- a/sys/dev/random/yarrow.c +++ b/sys/dev/random/yarrow.c @@ -38,6 +38,7 @@ #include <sys/libkern.h> #include <sys/malloc.h> #include <sys/proc.h> +#include <sys/select.h> #include <sys/random.h> #include <sys/time.h> #include <sys/types.h> @@ -45,8 +46,8 @@ #include <machine/mutex.h> #include <crypto/blowfish/blowfish.h> -#include <dev/randomdev/hash.h> -#include <dev/randomdev/yarrow.h> +#include <dev/random/hash.h> +#include <dev/random/yarrow.h> /* #define DEBUG */ /* #define DEBUG1 */ /* Very noisy - prints plenty harvesting stats */ @@ -65,11 +66,11 @@ TAILQ_HEAD(harvestqueue, harvest) harvestqueue, initqueue = TAILQ_HEAD_INITIALIZER(harvestqueue); /* These are used to queue harvested packets of entropy. The entropy - * buffer size of 16 is pretty arbitrary. + * buffer size is pretty arbitrary. */ struct harvest { struct timespec time; /* nanotime for clock jitter */ - u_char entropy[16]; /* the harvested entropy */ + u_char entropy[HARVESTSIZE]; /* the harvested entropy */ u_int size, bits, frac; /* stats about the entropy */ enum esource source; /* stats about the entropy */ u_int pool; /* which pool this goes into */ @@ -79,19 +80,18 @@ struct harvest { /* The reseed thread mutex */ static struct mtx random_reseed_mtx; -/* The entropy harvest mutex */ +/* The entropy harvest mutex, as well as the mutex associated + * with the msleep() call during deinit + */ static struct mtx random_harvest_mtx; -/* <0 until the kthread starts, 0 for running */ -static int random_kthread_status = -1; - /* <0 to end the kthread, 0 to let it run */ static int random_kthread_control = 0; static struct proc *random_kthread_proc; static void -random_kthread(void *status) +random_kthread(void *arg /* NOTUSED */) { int pl, src, overthreshhold[2]; struct harvest *event; @@ -101,10 +101,8 @@ random_kthread(void *status) #endif #ifdef DEBUG - printf("At %s, line %d: mtx_owned(&Giant) == %d\n", __FILE__, __LINE__, mtx_owned(&Giant)); - printf("At %s, line %d: mtx_owned(&sched_lock) == %d\n", __FILE__, __LINE__, mtx_owned(&sched_lock)); + printf("At %s, line %d: mtx_owned(&Giant) == %d, mtx_owned(&sched_lock) == %d\n", __FILE__, __LINE__, mtx_owned(&Giant), mtx_owned(&sched_lock)); #endif - random_set_wakeup((int *)status, 0); for (pl = 0; pl < 2; pl++) yarrow_hash_init(&random_state.pool[pl].hash, NULL, 0); @@ -148,9 +146,6 @@ random_kthread(void *status) source->frac %= 1024; free(event, M_TEMP); - /* XXX abuse tsleep() to get at mi_switch() */ - /* tsleep(&harvestqueue, PUSER, "rndprc", 1); */ - } #ifdef DEBUG1 printf("Harvested %d events\n", queuecount); @@ -177,7 +172,7 @@ random_kthread(void *status) } /* Is the thread scheduled for a shutdown? */ - if (random_kthread_control < 0) { + if (random_kthread_control != 0) { if (!TAILQ_EMPTY(&harvestqueue)) { #ifdef DEBUG printf("Random cleaning extraneous events\n"); @@ -192,7 +187,8 @@ random_kthread(void *status) #ifdef DEBUG printf("Random kthread setting terminate\n"); #endif - random_set_wakeup_exit((int *)status, -1, 0); + random_set_wakeup_exit(&random_kthread_control); + /* NOTREACHED */ break; } @@ -223,13 +219,13 @@ random_init(void) mtx_init(&random_harvest_mtx, "random harvest", MTX_DEF); /* Start the hash/reseed thread */ - error = kthread_create(random_kthread, &random_kthread_status, + error = kthread_create(random_kthread, NULL, &random_kthread_proc, RFHIGHPID, "random"); if (error != 0) return error; /* Register the randomness harvesting routine */ - random_init_harvester(random_harvest_internal); + random_init_harvester(random_harvest_internal, read_random_real); #ifdef DEBUG printf("Random initalise finish\n"); @@ -253,9 +249,11 @@ random_deinit(void) #endif /* Command the hash/reseed thread to end and wait for it to finish */ + mtx_enter(&random_harvest_mtx, MTX_DEF); random_kthread_control = -1; - while (random_kthread_status != -1) - tsleep(&random_kthread_status, PUSER, "rndend", hz); + msleep((void *)&random_kthread_control, &random_harvest_mtx, PUSER, + "rndend", 0); + mtx_exit(&random_harvest_mtx, MTX_DEF); #ifdef DEBUG printf("Random deinitalise removing mutexes\n"); @@ -364,10 +362,16 @@ reseed(int fastslow) printf("Reseed finish\n"); #endif + if (!random_state.seeded) { + random_state.seeded = 1; + selwakeup(&random_state.rsel); + wakeup(&random_state); + } + } u_int -read_random(void *buf, u_int count) +read_random_real(void *buf, u_int count) { static u_int64_t genval; static int cur = 0; @@ -430,19 +434,19 @@ write_random(void *buf, u_int count) u_int i; struct timespec timebuf; - /* arbitrarily break the input up into 8-byte chunks */ - for (i = 0; i < count; i += 8) { + /* arbitrarily break the input up into HARVESTSIZE chunks */ + for (i = 0; i < count; i += HARVESTSIZE) { nanotime(&timebuf); - random_harvest_internal(&timebuf, (char *)buf + i, 8, 0, 0, + random_harvest_internal(&timebuf, (char *)buf + i, HARVESTSIZE, 0, 0, RANDOM_WRITE); } /* Maybe the loop iterated at least once */ if (i > count) - i -= 8; + i -= HARVESTSIZE; - /* Get the last bytes even if the input length is not a multiple of 8 */ - count %= 8; + /* Get the last bytes even if the input length is not a multiple of HARVESTSIZE */ + count %= HARVESTSIZE; if (count) { nanotime(&timebuf); random_harvest_internal(&timebuf, (char *)buf + i, count, 0, 0, @@ -486,7 +490,6 @@ random_harvest_internal(struct timespec *timep, void *entropy, u_int count, u_int bits, u_int frac, enum esource origin) { struct harvest *event; - u_int64_t entropy_buf; #if 0 #ifdef DEBUG @@ -501,8 +504,8 @@ random_harvest_internal(struct timespec *timep, void *entropy, u_int count, event->time = *timep; /* the harvested entropy */ - count = count > sizeof(entropy_buf) - ? sizeof(entropy_buf) + count = count > sizeof(event->entropy) + ? sizeof(event->entropy) : count; memcpy(event->entropy, entropy, count); diff --git a/sys/dev/random/yarrow.h b/sys/dev/random/yarrow.h index a81fa1f..4bf97fd 100644 --- a/sys/dev/random/yarrow.h +++ b/sys/dev/random/yarrow.h @@ -36,16 +36,18 @@ #define ENTROPYBIN 256 /* buckets to harvest entropy events */ #define TIMEBIN 16 /* max value for Pt/t */ +#define HARVESTSIZE 16 /* max size of each harvested entropy unit */ + #define FAST 0 #define SLOW 1 int random_init(void); void random_deinit(void); -void random_init_harvester(void (*)(struct timespec *, void *, u_int, u_int, u_int, enum esource)); +void random_init_harvester(void (*)(struct timespec *, void *, u_int, u_int, u_int, enum esource), u_int (*)(void *, u_int)); void random_deinit_harvester(void); -void random_set_wakeup(int *, int); -void random_set_wakeup_exit(int *, int, int); +void random_set_wakeup_exit(void *); +u_int read_random_real(void *, u_int); void write_random(void *, u_int); /* This is the beastie that needs protecting. It contains all of the @@ -70,6 +72,8 @@ struct random_state { struct yarrowhash hash; /* accumulated entropy */ } pool[2]; /* pool[0] is fast, pool[1] is slow */ int which; /* toggle - shows the current insertion pool */ + int seeded; /* 0 until first reseed, then 1 */ + struct selinfo rsel; /* For poll(2) */ }; extern struct random_state random_state; |
